Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

readOnlyHint=true already tells the agent this is a safe read, so the description's job is lighter. It adds that results include status, totals and client and names the backing endpoint (GET /v1/invoices), but says nothing about pagination behavior, default page size, or result ordering.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences, zero padding, with the resource and return fields front-loaded before the endpoint reference. Nothing could be removed without losing content.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a read-only list tool with full annotation safety coverage and no output schema, the description gives enough to call it: resource, return fields, endpoint. The main residual gap is pagination guidance, though the cursor and page_size params cover it structurally.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 82%, so the schema already explains cursor, page_size, query and the date filters. The description contributes no additional parameter meaning; a brief note that filters combine (e.g. status_ids + due_date_before) would have added value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ("List invoices") and adds what the rows carry (status, totals, client). It does not distinguish itself from the sibling gorelo_get_invoice (single-record fetch), leaving that routing to inference.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No statement of when to use this versus gorelo_get_invoice or gorelo_list_contracts, no prerequisites, no exclusions. The only usage-adjacent hint ("find overdue invoices") lives in the schema for due_date_before, not in the description.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.